nc临时开启端口并监听

port="6379  3306 27017 4505 4506 24007 24008 49152"

#while  true
#do
  sleep 3
for i in $port
do
  isexist=`netstat -lntup|grep 3306|head -n 1|awk ‘{print $4}‘`
  if [ ! $isexist ];then
    echo $i
    ports="$ports $i"
  fi
done
echo $ports



for i in $ports
do
  nc -lk $i &
done
# 显示端口状态
for i in $port
do
  netstat -lntup|grep $i
done

#done